In order to characterize the polarization states generated by our LCs, we can rotate the output polarizer while applying different voltages to our LC.

As our motorized rotator is from Thorlabs, we had to switch the position of our input and output polarizers.

We estimated the extinction ratio of our polarizers to be about 25 000 each.

Then, we calibrated again each LCs as shown in fig 1 and 2 for LC1 and 3 and 4 for LC2.

Their respective fast axis direction is 45.74 deg and 69.00 deg.

From figures 2 and 4, the maximum retardation at these angles is below 6 nm offset from 532 nm which indicates a misalignment of about 0.01 deg from the fast axis from simulation.